The apostle fully establishes the truth throughout this epistle that a man is justified before God by faith and not by works. In these verses he shows in the most decisive manner that Abraham did not obtain Justification by circumcision, since he was justified BEFORE he was circumcised! Justification has no necessary connection with, or dependence on, circumcision. WE ARE SAVED BY FREE GRACE!
(Vs. 9) Is justification only for the circumcised Jew or for the Gentile as well? Why does Paul ask a question such as this? Because the Jews not only believed that justification before God depended (at least in part) on their works, but that this blessing was connected with circumcision, therefore for the Jew only! The design of the following words is to prove that justification belongs to Gentile and Jew, and that it is by faith and not by circumcision. Abraham serves as the example.
(Vs. 10) When was Abraham justified? If righteousness was imputed to him BEFORE he was circumcised, then circumcision was not the cause, nor is it necessary to justification. And it may come on the Gentile as well as on Jews. According to the Scriptures he was in a state of righteousness and justification before the birth of Ishmael (Gen. 15:6; 17:1-4; 17:9-14; 17:24-25).
(Vs. 11-12) If Abraham was justified before he was circumcised, then why was he circumcised? (1) Ills circumcision and the circumcision of all Jews was a sign or token of that covenant which God made with Abraham and his natural seed concerning the enjoyment of the land and His favor. It distinguished them from all other nations (Gen. 17:8-11). (2) Circumcision is also a typical sign of Christ (as all the ceremonies of the Law were), of the shedding of His blood to cleanse from sin and the circumcision of the heart. (3) It was a seal to Abraham that he should be the father of many nations in a spiritual sense and that the righteousness of faith (which he had) should come upon them, Gentile and Jew, after the same manner--by faith (Rom. 4:23-24). While all of Abraham's natural seed were circumcised, it was only to those who had his faith that he was a father in what is spiritually represented by circumcision.
(Vs. 13) "Heir of the world" means this world and the world to come. Abraham and all believers are the heirs of all things in Christ (I Cur. 3:21-23; Heb. 11:8-10, 13; Luke 20:34-36).
"Or to His seed." The covenant, in all its promises in reference to spiritual-blessings, was established in Christ, who was Abraham's seed (Gal. 3:16), and was given to all His church in Christ (Rom. 8:16-17).
"Not through the law but through faith." Not through the Law of Moses, nor the law of ceremony, nor the law of circumcision, but by faith in Christ (Gal. 3:21-22).
(Vs. 14-15) If the Jews, who were seeking righteousness and eternal life by the works of the Law, should on account of their obedience to the Law obtain grace and glory, then FAITH IS SET ASIDE: and the promise of righteousness by faith is of no effect. If salvation is by works, it is useless for God to promise life to those who, because of their inability to keep the Law, seek it by faith. Salvation cannot be by faith and works (Gal. 3:18; Gal. 2:21).
It is the LAW BROKEN that brings upon us the wrath of God. The Law not only cannot Justify (because of man's sinful state) but it curses and condemns the guilty (Rom. 3:19; Rom. 8:3-4).
"Where no law is there is no transgression." This is sort of a proverbial expression. Sin is the transgression of God's Law. But the Law IS COME! Not only the written Law, but that law which is revealed through creation, conscience, and written on the heart.
(Vs. 16) Therefore, righteousness and justification are of faith and not of works. In no other way but through faith can salvation be by grace (Rom. 11:6). A reward must be reckoned either all of grace or else all of debt on account of works performed; these cannot be combined. If God takes into account any works of men, then salvation is not by grace.
Also, the only way that salvation can be sure and the promise of eternal life certain, for Jew or Gentile, is for the whole of the work to be by the grace of God. We are born sinners, by practice and choice we have failed, and the future holds no hope for us apart from His grace (Gal. 3:10; Gal. 4:21; James 2:10).